This invention relates to a cooling system for a liquid-cooled type of two-cycle multicylinder engine.
There are certain prior art cooling systems in which the delivery port of a water pump mounted on one end of a crank shaft is flow connected to a water passage within a crank case, which is further flow connected directly to a water jacket within a cylinder block for eliminating any piping arrangement. However, such conventional cooling systems require an increase in wall thickness of a portion of the crank case to provide therein the water passage in the axial direction of the crank shaft, and hence had a disadvantage that the crank case becomes greater in size. Furthermore, the water pump mounted on the end of the crank shaft increased disadvantageously the overall length of the engine in the axial direction of the crank shaft.
The prior art to which the invention is directed also includes another type of cooling systems in which cooling hoses are used for piping. Such cooling systems require longer and complicated piping because of a number of hoses extending along the outside of an engine, which resulted in increase in the number of parts and higher cost for manufacturing.